DENVER — On Wednesday morning, Sean Azzariti became the first person in the nation — and potentially the world, experts say — to buy marijuana for recreational use under a regulated, sanctioned system. The former marine who served twice in Iraq helped to make history, but his involvement on New Year’s Day reflected another change: the professionalization of a multi-million dollar industry that just 20 years ago was fully underground.

Azzariti turned to pot after receiving prescriptions for daily doses of 6mg of Xanax, 4mg Klonopin, and 30-50 mg of Adderall to deal with post-traumatic stress disorder, he said. “I just looked at this cocktail, and I was like I just can’t do this. Absolutely no way. I’d just be a drug addict,” he says. “[Cannabis] saved my life, basically.”

His involvement was part of an organized media event hosted by the industry — a reflection of a business that, after emerging from the shadows, is becoming increasingly professional. Store owners talk about $100,000 investments and expanding by tens of thousands of square feet. Even the profile of the business people involved has changed. A few years ago, most in the medicinal marijuana business had a high risk for tolerance or extraordinary passion for the work, says National Cannabis Industry Association Deputy Director Betty Aldworth.

Read more: Marijuana legalization in Colorado reflects a maturing industry | Washington Post.